BABE: THE SULTAN OF PITCHING STATS? by Matthew H. LoRusso Paul M. Sommers August 2010 MIDDLEBURY COLLEGE ECONOMICS DISCUSSION PAPER NO. 10-30 DEPARTMENT OF ECONOMICS MIDDLEBURY COLLEGE MIDDLEBURY, VERMONT 05753 http://www.middlebury.edu/~econ
2 BABE: THE SULTAN OF PITCHING STATS? by Matthew H. LoRusso Paul M. Sommers Department of Economics Middlebury College Middlebury, Vermont 05753 psommers@middlebury.edu
3 BABE: THE SULTAN OF PITCHING STATS? I Got You Babe Sonny & Cher, 1965 There is no shortage of baseball metrics. Perhaps the most popular measure of pitching performance is the earned run average (ERA). ERA is equal to the number of earned runs a pitcher gives up in a nine-inning game. An alternative measure of pitcher performance is the number of walks plus hits allowed by a pitcher divided by the number of innings pitched (with the acronym WHIP). Since singles and extra-base hits are treated alike, WHIP is somewhat flawed. A relative newcomer to the fan s kitbag of statistical tools is the BABE, which unlike WHIP, adds the number of total bases a pitcher gives up to the number of walks allowed and divides this sum by the number of batters faced. 1,2 More precisely, the BABE is given by: TB BB AB BB where TB denotes the opposing team s total bases, BB is the opponent s bases on balls or walks, and AB represents the opponent s number of at bats. The lower the BABE, the better the pitcher s performance. In this brief research note, we examine all 369 games in all World Series played between 1946 and 2009. Postseason data on total bases, walks, and at bats (gleaned from the box scores) of each game for each team each year are from www.baseball-reference.com. How well does this defensive measure alone predict outcomes? Were the BABEs of winning teams in the World Series significantly lower than the BABEs of their opponents? Did the series (or individual game) winner have the lower BABE more than half the time? And, have the BABEs of winning or losing teams in the World Series changed between the pre-free agency (1946-1976) and post-free agency (1977-2009) periods? Table 1 shows the BABEs of the eventual winner and loser in each World Series between 1946 and 2009. Of the 63 World Series, the eventual series winner had the lower BABE two-thirds of the time. All but one of the 21 exceptions (11 American League or AL series winners, 10 National League or NL series
winners) involved a 6- or 7-game series. Table 2 shows that in four-game sweeps or a World Series that ended in only five games, the eventual series winner (both before and after 1977, the beginning of free agency) had significantly lower average BABEs. 3 In a 6- or 7-game series, the average BABEs of winners and losers were indistinguishable (at the.05 level of significance). Between 1946-1976 and 1977-2009, the BABEs of losing teams (regardless of the length of the series) generally rose, especially for teams that were swept in four games. Of the 369 games played in a World Series between 1946 and 2009, an individual game winner had the lower BABE 83.2 percent (or 307/369) of the time. 4,5 Table 3 shows that individual game winners had significantly smaller BABEs than game losers over the entire 64-year period, as well as in the two shorter sub-periods. One would think that managers used relief pitchers more frequently between 1977 and 2009 than they did in the earlier period (when starting pitchers were expected to pace themselves for a full game). That is, the rise in relief pitching should have a negative impact on the opponent s long-ball hitting. BABEs should be lower now than they were before. Yet, BABEs of winners and losers are, on average, significantly higher in the 1977-2009 period than they were in the earlier period, especially for AL winners and NL losers. Finally, there appears to be little (if any) home field impact on BABEs. The BABE of a home win (loss) is no different from the BABE of a road win (loss) [p =.750 (p =.945)]. Curiously, in the more recent period, when NL teams lose on the road (playing in an AL ballpark under AL rules which allow for designated hitters), the average BABE of NL team losers is significantly higher than the average BABE of AL team losers (p =.033). Concluding Remarks For pitchers, games won per season, the strikeout-to-walk ratio, and ERA are among the performance measures that first come to mind. WHIP is less common. And, the newborn BABE (bases per batter) is shown to be closely related to club wins in World Series play. In particular, the BABEs of winning teams in the World Series were significantly lower than the BABEs of losing teams since 1946, both before and after free agency, a result that underscores the belief that pitching wins championships.
5 Table 1. BABEs, World Series, 1946-2009 Number of Winner s Winner s Loser s Number of Winner s Winner s Loser s Year Games Affiliation BABE 1 BABE Year Games Affiliation BABE 1 BABE 1946 7 NL.3882.4183 1978 6 AL.4475.4244 1947 7 AL.3906.5000 1979 7 NL.4015.4719 1948 6 AL.3793.3399 1980 6 NL.5279.4444 1949 5 AL.3955.4121 1981 6 NL.4734.4450 1950 4 AL.3037.3649 1982 7 NL.4436.4566 1951 6 AL.3927.4489 1983 5 AL.3373.4080 1952 7 AL.3852.4563 1984 5 AL.4011.4890 1953 6 AL.5175.5398 1985 7 AL.3248.4470 1954 4 NL.3791.4014 1986 7 NL.4601.4330 1955 7 NL.4467.5000 1987 7 AL.3551.4869 1956 7 AL.3765.4840 1988 5 NL.3086.4389 1957 7 NL.4325.4089 1989 4 AL.3803.6280 1958 7 AL.4045.4213 1990 4 NL.3605.5223 1959 6 NL.4292.4233 1991 7 AL.4764.4466 1960 7 NL.5575.3862 1992 6 AL.3591.4159 1961 5 AL.3371.5132 1993 6 AL.5041.5628 1962 7 AL.3866.3388 1994 * 2 * * * 1963 4 NL.2687.4063 1995 6 NL.3818.4862 1964 7 NL.4773.4186 1996 6 AL.4330.3689 1965 7 NL.3846.4211 1997 7 NL.5122.4965 1966 4 AL.2707.3969 1998 4 AL.4247.5409 1967 7 NL.4059.3984 1999 4 AL.3517.4667 1968 7 AL.4462.4535 2000 5 AL.3817.4804 1969 5 NL.2791.3600 2001 7 NL.3347.4335 1970 5 AL.4078.5602 2002 7 AL.5547.5112 1971 7 NL.3556.4167 2003 6 NL.4629.3456 1972 7 AL.3725.3568 2004 4 AL.3623.5556 1973 7 AL.4007.3829 2005 4 AL.4063.5325 1974 5 AL.4023.3924 2006 5 NL.3669.4254 1975 7 NL.4424.4461 2007 4 AL.3916.5813 1976 4 NL.3401.5616 2008 5 NL.3554.5538 1977 6 AL.4554.4398 2009 6 AL.5273.4491 1 Numbers in italics indicate that the winner s BABE was greater than the loser s BABE (occurred 21 times, 11 AL winners, 10 NL winners). 2 The 1994-95 strike caused the cancellation of the 1994 World Series.
6 Table 2. Difference between BABEs, by Length of Series, 1946-2009 p-value Average BABE on Group 1 Group 2 Group 1 Group 2 difference 1 4-game series Winner Loser.3533.4965 <.001 Winner, 1946-1976 Loser, 1946-1976.3124.4262.015 Winner, 1977-2009 Loser, 1977-2009.3825.5467 <.001 5-game series Winner Loser.3611.4576 <.001 Winner, 1946-1976 Loser, 1946-1976.3644.4476.042 Winner, 1977-2009 Loser, 1977-2009.3585.4659.002 6-game series Winner Loser.4494.4381.738 Winner, 1946-1976 Loser, 1946-1976.4297.4380.356 Winner, 1977-2009 Loser, 1977-2009.4572.4382.788 7-game series Winner Loser.4199.4381.092 Winner, 1946-1976 Loser, 1946-1976.4149.4240.293 Winner, 1977-2009 Loser, 1977-2009.4292.4648.084 1 Paired one-tailed t-tests under the alternative hypothesis: Average of Group 1 < Average of Group 2.
7 Table 3. Difference between BABEs, Individual Games in World Series, 1946-2009 p-value Average BABE on Group 1 Group 2 Group 1 Group 2 difference 1 Game winner Game loser.3538.4909 <.001 Winner, 1946-1976 Loser, 1946-1976.3386.4747 <.001 Winner, 1977-2009 Loser, 1977-2009.3696.5078 <.001 Winner, 1946-1976 Winner, 1977-2009.3386.3696.012 AL Winner, 1946-1976 AL Winner, 1977-2009.3325.3759.010 NL Winner, 1946-1976 NL Winner, 1977-2009.3453.3614.381 Loser, 1946-1976 Loser, 1977-2009.4747.5078.009 AL Loser, 1946-1976 AL Loser, 1977-2009.4710.5016.113 NL Loser, 1946-1976 NL Loser, 1977-2009.4781.5125.042 Home Win Road Win.4036.3990.750 AL Home Win NL Home Win.3981.4099.570 AL Road Win NL Road Win.3973.4011.853 Home Loss Road Loss.4424.4434.945 AL Home Loss NL Home Loss.4197.4605.051 AL Road Loss NL Road Loss.4396.4467.705 AL Road Win, NL Road Win, 1946-1976 1946-1976.3809.3881.801 AL Road Win, NL Road Win, 1977-2009 1977-2009.3966.4270.323 AL Road Loss, NL Road Loss, 1946-1976 1946-1976.4327.3907.129 AL Road Loss, NL Road Loss, 1977-2009 1977-2009.4469.4972.033 1 For the first three comparisons involving winners (Group 1) and Losers (Group 2), see footnote 1 in Table 2. All other p-values are based on a two-tailed t-test.
8 Reference 1. Allen St. John, By the Numbers, The Wall Street Journal, August 13, 2004, p. W5.
9 Footnotes 1. The first mention of BABE appears in [1]. 2. As for baseball s other Babe, Ruth s career began in 1914 as a left-handed pitcher for the Boston Red Sox. In six years on the mound at Fenway Park (before that now infamous sale to the New York Yankees), Babe won 89 regular season games and three World Series games (one win in 1916 and two wins in 1918). 3. Between 1946 and 1976, four rule changes were introduced into baseball that would be expected to affect batting and pitching performance statistics. In 1950, the strike zone was narrowed. In 1963, the strike zone was widened. In 1969, the strike zone was again narrowed. In 1973, the American League introduced the Designated Hitter rule but the National League did not. 4. The BABE of the game winner was greater than that of the loser on eight occasions in Game 1, twelve in Game 2, thirteen in Game 3, and fifteen in Game 4. (All four games were contested 63 times between 1946 and 2009.) The BABE of the winner exceeded that of the loser eight times in Game 5 (of 51 times Game 5 was contested) and three times each in Games 6 (40) and 7 (26). 5. BABE was equal to zero only once, in Don Larsen s perfect game (Game 5) in the 1956 World Series. The highest value of BABE was.8837 in Game 5 of the 1991 World Series, when the Atlanta Braves (the ultimate series loser) defeated the Minnesota Twins 14-5.